Kids ask a pile of questions .
mental_flosshas answers . This calendar week we launch WHY ? , our new series for small fry and parents . We ’ll tackle all types of questions children have about how the worldly concern mould by provide scientific discipline - based , youngster - well-disposed content . Our answers are spell with early reader ( ages 4 to 7 ) in mind , but we call back they ’re interesting — and educational — for everyone .
Have a question ? place it to why@mentalfloss.com .
Air surrounds the surface of the Earth . breeze is a mixing ofgases : 78 percent nitrogen , 21 percent atomic number 8 , 1 percent argon , a little mo of carbon paper dioxide , and flyspeck amounts of 13 other gun . Plus , air containswater vapor , a mix of hydrogen and oxygen . Airis the part of the atmosphere close to the Earth . Like a big blanket surrounding Earth , the atmosphere observe us from commence too blistering from the sunlight or too cold from space — and allows us to take a breather .
Land animals ca n’t exist without the oxygen in the air . More than 2.3 billion years ago the atmosphere was mostly nitrogen . But then the number of tiny microbes calledcyanobacteria(SIGH - an - oh - back - TEER - e - uh ) grew . Cyanobacteria use sunlight to convert C dioxide into a kind of intellectual nourishment — a cognitive process calledphotosynthesis . The waste material Cartesian product of photosynthesis isoxygen . So much O was created that it begin to fill up the atmosphere . After time , more animals evolved that wereaerobic(air - OH - bick ) , meaning they need oxygen to survive — like us .
Because flora photosynthesize ! think , atomic number 8 is a wastefulness product of photosynthesis , and an important part of breeze . Without oxygen , we ca n’t breathe . Thanks for making oxygen , plants ! But we do something for plants too . We breathe out carbon dioxide , which constitute win over into round-eyed intellectual nourishment . So plant life and beast function together to keep all creatures alive . How cool is that ?
For playfulness further reading about photosynthesis , jaw thisgardening guide for kidsfrom the BBC .
